Improvement of acrylic-urethane paint adhesion to PP-EPDM surface by mediated electrochemical oxidation

Document Type : Article

Authors

Iran Polymer and Petrochemical Institute, P.O. Box 14965/115, Tehran, Iran

10.24200/sci.2020.53396.3220

Abstract

Adhesion improvement of an acrylic-urethane paint on a bumper surface made from polypropylene/ethylene-propylene-diene monomer was investigated at long term after electrochemical treatment by 2N nitric acid and 0.6M Silver (II)-nitrate /2N nitric acid. The stability of the electrochemically treated samples was examined at different aging times by ATR and SEM. The results were also compared to those of the untreated and flame-treated samples. Accelerated UV weathering analysis along with morphology study by SEM approved the effectiveness of the Ag (II) treatment technique in long term particularly at curvature area of the bumper. For the Ag (II) treated samples, the increase in adhesion strength was sustained even after 650 hours exposure to UV irradiation in wet condition prior to bonding. In addition, the stability of the Ag (II)-treated surface was maintained for at least three months. In case of the flame-treated surface, hydrophobic recovery during aging in environment was found to reduce the polarity of the PP-EPDM surface. The pull-off test showed Ag (II) treatment can enhance adhesion strength of the acrylic-urethane coating on to PP-EPDM in comparison with the flaming method by 20.7%. Moreover the results of zeta potential analysis for Ag (II) treated blend showed a typical acidic surface.

Keywords


1. Mart__nez, C. and Panizza, M. Electrochemical oxidation of organic pollutants for waste watertreatment", Current Opinion in Electrochemistry, 11, pp. 62{67 (2018). 2. Nickerson, R. Plasma surface modi_cation for cleaning and adhesion", Polymers Laminations And Coatings Conference, pp. 1101{1108 (1998). 3. Brewis, D. and Dahm, R. A review of electrochemical pretreatments of polymers", International Journal of Adhesion and Adhesives, 21(5), pp. 397{409 (2001). 4. Cust_odio, J., et al. Activation of timber surfaces by ame and corona treatments to improve adhesion", International Journal of Adhesion and Adhesives, 29(2), pp. 167{172 (2009). 5. Farris, S., et al. The fundamentals of ame treatment for the surface activation of polyole_n polymers", Polymer, 51, pp. 3591{3605 (2010). 6. Fazeli, M., Florez, J.P., and Sim~ao, R.A. Improvement in adhesion of cellulose _bers to the thermoplastic starch matrix by plasma treatment modi_cation", Composites Part B: Engineering, 163, pp. 207{216 (2019). 7. Fazeli, M. and Sim~ao, R.A. The e_ect of cellulose nano_bers on the properties of starch biopolymer", In Macromolecular Symposia, 380(1), pp. 1{8 (2018). 8. Buend__a, J.J. and Fabregat, G. Plasma-treated polyethylene as electrochemical mediator for enzymatic glucose sensors", Plasma Processes and Polymers, 15(1), pp. 1{10 (2018). 9. Cabrera, F., Dognani, G., Santos, R.J., et al. Surface modi_cation of natural rubber by sulfur hexauoride (SF6) plasma treatment: A new approach to improve mechanical and hydrophobic properties", Journal of Coating Science and Technology,3(3), pp. 116{120 (2016). 10. Williams, D.F. Flame treatment of polypropylene: A study by electron and ion spectroscopies", International Journal of Adhesion and Adhesives, 63, pp. 26{ 33 (2015). 11. Strobel, M. A comparison of corona-treated and ame-treated polypropylene _lms", Plasmas and Polymers, 8(1), pp. 61{95 (2003). 12. Mokhtari, S., Mohammadi, F., and Nekoomanesh, M. Mediated electrochemical degradation of polystyrene by silver (II): optimization and kinetic studies", International Journal of ChemTech Research, 5, pp. 2656{ 2671 (2013). 13. Chashmejahanbin, M., Salimi, A., and Ershad Langroudi, A. The study of the coating adhesion on PP surface modi_ed in di_erent plasma/acrylic acid solution", International Journal of Adhesion and Adhesives, 49, pp. 44{50 (2014). 14. Brewis, D., Briggs, D., Dahm, R., and Fletcher, A. ToF-SIMS study of electrochemical pretreatments for polymers", Surface and Interface Analysis, 29(9), pp. 572{581 (2000). 15. Briggs, D., Brewis, D., Dahm, R., and Fletcher, I. Analysis of the surface chemistry of oxidized polyethylene: comparison of XPS and ToF-SIMS", Surface and Interface Analysis, 35(2), pp. 156{167 (2003). 16. Brewis, D., Dahm, R., and Mathieson, I. Electrochemical pretreatment of polymers with dilute nitric acid either alone or in the presence of silver ions", The Journal of Adhesion, 72(3), pp. 373{386 (2000). 17. Mokhtari, Sh., Mohammadi, F., and Nekoomanesh, M. Surface modi_cation of PP-EPDM used in automotive industry by mediated electrochemical oxidation", Iranian Polymer Journal, 25(4), pp. 309{320 (2016). 18. Ronagh-Baghbani, M., Naderi, G., and Mohammadi, F. Mediated electrochemical oxidation of vulcanized polybutadiene/organoclay nanocompositecharacterization and kinetic study", Polymer Degradation and Stability, 131, pp. 30{41 (2016). 19. Mokhtari, Sh., Mohammadi, F., and Nekoomanesh, M. Surface modi_cation of vulcanized EPDM rubber by Ag (II): Kinetic study of Ag (II) generation and surface characterization", Scientia Iranica, 25(3), pp. 1371{ 1383 (2018). 20. Ronagh-Baghbani, M., Naderi, G., and Mohammadi, F. Surface characterization of polybutadiene and natural rubbers oxidized by silver (II)", Soft Materials, 14(3), pp. 187{198 (2016). 21. Mokhtari, Sh., Mohammadi, F., and Nekoomanesh, M. E_ect of process parameters on the concentration, current e_ciency and energy consumption of electrogenerated silver (II)", Chemical Papers, 69(9), pp. 1219{1230 (2015). Sh. Mokhtari et al./Scientia Iranica, Transactions C: Chemistry and ... 27 (2020) 1253{1263 1263 22. Grundke, K., Jacobasch, H-J., Simon, F., and Schneider, S. Physico-chemical properties of surfacemodi _ed polymers", Journal of Adhesion Science and Technology, 9(3), pp. 327{350 (1995). 23. Basak, G.C. Surface modi_cation of argon/oxygen plasma treated vulcanized ethylene propylene diene polymethylene surfaces for improved adhesion with natural rubber", Applied Surface Science, 257(7), pp. 2891{2904 (2011). 24. Zeiler, T., Kellermann, S., and Munstedt, H. Different surface treatments to improve the adhesion of polypropylene", Journal of Adhesion Science and Technology, 14(5), pp. 619{634 (2000). 25. Vogel, A.I., A Text-Book of Quantitative Inorganic Analysis-Theory and Practice, Chap. 2, pp. 89{116, Wiley (2013). 26. Newman, C.R. and Forciniti, D. Modeling the ultraviolet photodegradation of rigid polyurethane foams", Industrial & Engineering Chemistry Research, 40(15), pp. 3346{3352 (2001). 27. Yousif, E. and Haddad, R., Photodegradation and Photostabilization of Polymers, Especially Polystyrene: Review, SpringerPlus, 2(1), pp. 398{430 (2013). 28. Rosu, D., Rosu, L., and Cascaval, C.N. IR-change and yellowing of polyurethane as a result of UV irradiation", Polymer Degradation and Stability, 94(4), pp. 591{596 (2009).